Dishwasher Smells When Running (Troubleshooting Guide)

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Quick answer
Confirm the symptom
Tools and prep
Step-by-step troubleshooting
Common causes table
Parts matching
When to call a pro
FAQ
Related guides

Quick answer

A smelly dishwasher is often caused by trapped food particles or mold. Clean the filter, rinse aid dispenser, and interior to eliminate odors. Run a vinegar or baking soda cycle for a deep clean.

Confirm the symptom

Dishwasher emits a foul smell during or after cycles
Odor is noticeable even after a wash cycle completes
Smell is not from dishes but from the machine itself

Tools and prep

Rubber gloves
White vinegar or baking soda
Soft brush or toothbrush
Clean cloth or sponge
Plastic scraper (optional)
Empty dishwasher racks

Step-by-step troubleshooting

Turn Off Power
Do: Unplug the dishwasher or turn off the circuit breaker.
Observe: Machine is powered down.
Means: Ensures safety during cleaning.
Next: Clean the filter
Clean the Filter
Do: Locate the filter at the bottom of the dishwasher and remove it. Rinse under running water and scrub with a soft brush.
Observe: Filter is free of food debris and grime.
Means: Clogged filters cause odors.
Next: Clean the interior
Clean the Interior
Do: Wipe down the interior walls, door, and seals with a damp cloth. Use a vinegar solution or baking soda paste to scrub stubborn areas.
Observe: Interior surfaces are clean and dry.
Means: Mold and mildew buildup can cause smells.
Next: Check the rinse aid dispenser
Check the Rinse Aid Dispenser
Do: Remove the rinse aid cap and clean the dispenser with a cloth. Ensure it is not clogged with residue.
Observe: Dispenser is clear and free of buildup.
Means: Clogged dispensers can trap moisture and cause odors.
Next: Run a cleaning cycle
Run a Cleaning Cycle
Do: Place a cup of white vinegar in a glass measuring cup on the top rack. Run a hot water cycle. Alternatively, sprinkle baking soda on the bottom and run a normal cycle.
Observe: Dishwasher completes the cycle without odors.
Means: Natural cleaners help remove lingering smells.
Next: Test the dishwasher
Test the Dishwasher
Do: Run a normal cycle with a load of dishes. Check for any remaining odors.
Observe: Dishwasher runs without foul smells.
Means: Problem is resolved.
Next: Final check

Common causes

Cause	Likelihood	Difficulty	Part often needed
Clogged Filter Food particles and grime trapped in the filter can rot and cause bad smells.	Common	Easy	Dishwasher filter (if damaged)
Mold and Mildew Moisture trapped in the dishwasher can lead to mold and mildew growth, especially in seals and corners.	Common	Easy	None
Clogged Rinse Aid Dispenser Residue buildup in the dispenser can trap moisture and cause odors.	Sometimes	Easy	Rinse aid dispenser (if damaged)
Blocked Drain Hose A kinked or clogged drain hose prevents proper drainage, leading to stagnant water and odors.	Sometimes	Medium	Drain hose or plumber's snake
Hard Water Deposits Mineral buildup can trap moisture and create a breeding ground for bacteria.	Sometimes	Easy–Medium	Water softener or descaling solution
Food Trapped in Spray Arms Food particles stuck in the spray arm holes can rot and cause odors.	Sometimes	Easy	Spray arms (if damaged)
Improper Ventilation Poor ventilation can cause moisture to linger, promoting mold and mildew growth.	Rare	Hard	Ventilation system or exhaust fan
Old or Expired Detergent Expired detergent can leave residue that causes odors.	Rare	Easy	New detergent

Parts matching

Common parts that may need replacement if damaged or worn:

Dishwasher filter
Rinse aid dispenser
Spray arms
Drain hose
Water softener or descaling solution

Inspect parts for damage or excessive wear during cleaning. Replace if necessary for long-term odor prevention.

When to call a professional

Persistent foul smell after multiple cleaning attempts
Visible mold or mildew that cannot be removed with regular cleaning
Dishwasher leaks water or has other mechanical issues
Drain hose is severely clogged and requires professional unclogging
Unusual noises accompany the smell, indicating internal damage

FAQ

How often should I clean my dishwasher to prevent odors?

Clean the filter and interior every 1–2 months. Run a vinegar or baking soda cycle every 1–2 months for maintenance.

Can using the wrong detergent cause odors?

Yes, using too much detergent or the wrong type can leave residue that causes odors. Follow manufacturer recommendations.

Why does my dishwasher smell like rotten eggs?

A rotten egg smell is often caused by bacterial growth in the drain hose or filter. Clean these areas thoroughly and ensure proper drainage.

Is it normal for my dishwasher to smell after a cycle?

No, a fresh scent is normal. A lingering foul smell indicates a buildup of food particles, mold, or poor drainage.

Can hard water cause dishwasher odors?

Yes, hard water can lead to mineral deposits that trap moisture and bacteria. Use a water softener or descaling solution to prevent this.